Set minSdkVersion to 21

example/android/build.gradle

@@ -3,10 +3,10 @@
 buildscript {
     ext {
         RNNKotlinVersion = "1.3.61"
-        buildToolsVersion = "29.0.2"
+        buildToolsVersion = "30.0.0"
         minSdkVersion = 21
-        compileSdkVersion = 29
-        targetSdkVersion = 29
+        compileSdkVersion = 30
+        targetSdkVersion = 30
     }
     repositories {
         google()
@@ -14,7 +14,7 @@ buildscript {
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.61"
-        classpath("com.android.tools.build:gradle:3.5.3")
+        classpath("com.android.tools.build:gradle:4.1.2")
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files